Small animals are routinely used in the research setting. It is often of interest to record the electrocardiogram from mice and rats, as well as other rodents such as hamsters and guinea pigs. Given their high level of activity when they are awake, ECGs are often recorded when the animals are under anesthesia. Alternatively, telemetric transmitters are implanted, which communicate wirelessly with receivers, to provide the ECG in conscious awake mice, after they recover from the implantation procedure.
The implants and ancillary recording equipment are expensive, however. One known alternative is to record an ECG in a conscious rodent by placing the animal atop an instrumented platform whereby the ECG signal is detected passively through the underside of their paws. One limitation of this paradigm, however, is the relatively short window of time during which the ECG recordings are made. For example, mice or other rodents occasionally escape from the elevated platform, thereby breaking the electrical connection and evading measurement.